Accession Number : AD0683329

Title :   THE SHAPE OF TWO-DIMENSIONAL TURBULENT WAKES IN DENSITY-STRATIFIED FLUIDS.

Descriptive Note : Final rept.,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE HYDRODYNAMICS LAB

Personal Author(s) : Monroe,Roy Hayden , Jr. ; Mei,C. C.

Report Date : JUN 1968

Pagination or Media Count : 85

Abstract : The results of an analytical and experimental investigation of the rate of growth of the zone of turbulent mixing behind a two-dimensional circular cylinder are presented. The analytical phase of the study formulated a dynamical model for a parcel of fluid subjected to inertia, turbulent damping, and gravity restoring forces. The experiments were conducted in a tank 120 in. long and 4.5 in. wide which was filled to a depth of 18 in. with a fluid having a linear density gradient. The cylinder was towed at mid-depth by a variable speed motor-pulley system. A record of wake growth behind the cylinder was made by means of motion pictures of an aluminum pigment tracer in the fluid. The Reynolds number ranged from 1300 to 3500 and densimetric Froude numbers varied from 5 to 20. The density stratification was found to exert a strong inhibiting force on the wake growth. Using the dynamical model to correlate experimental data, the mixing length in the turbulent zone was found to decrease with increasing density stratification. (Author)

Descriptors :   (*WAKE, GEOMETRIC FORMS), (*TWO DIMENSIONAL FLOW, WAKE), FLUID FLOW, DENSITY, TURBULENCE, CYLINDRICAL BODIES, INERTIA, DAMPING, GRAVITY, TOWED BODIES, REYNOLDS NUMBER, INHIBITION

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE